Sunday, 10 June 2018

Gigabit LTE- A stepping stone for 5G readiness.

As we said earlier that Gigabit LTE is going to be a stepping stone for 5G readiness of the networks. What could be a better example than the recent news from Russia where MTS upgraded its network with LAA capabilities using Ericsson equipment’s and test the gigabit LTE speed on commercial deployments with commercial UEs.

LAA is an important technology in the LTE network evolution to 5G, providing access to new unlicensed frequencies. With this milestone, MTS has surpassed its previous 700Mbps speed record, enabling the service provider to take the next step in turning its mobile infrastructure into gigabit-capable.

The deployment took place in a large trade center on May 17 following a series of tests conducted on a live MTS network using a commercial smartphone. The gigabit-per-second speeds were achieved using Ericsson Radio System software, including 256-QAM and 4CC Carrier Aggregation of 10 streams with 4x4 MIMO on a 20MHz licensed carrier coupled with 3x20MHz LAA.

In addition, a range of Ericsson Radio System products including the LAA-powered Radio 2205, Baseband 5216, and B3 1800MHz band configured Radio 2212 were used in the rollout.  Mobile devices powered by the Qualcomm® Snapdragon™ Gigabit LTE modems with LAA support, including Snapdragon 835 and 845 Mobile Platforms.

While talking the Gigabit LTE, the first picture emerges about a gigabit speed on each UE terminals, or at least a speed of gigabit per second peek rates.  Although, as in above case, operators are able to achieve it with the technology called ‘Carrier Aggregation’, in specific form called LAA, and MIMO with optimized coding and modulation schemes.

But it also shows the whole scenario to be highly optimized to achieve such data rates, which in practicality not always feasible, so what is the big buzz about gigabit LTE, with this Question in mind we approached our Experts (Mr Oscar Bexell) and discussed at large and some significant take away we gleaned are like this…

Gigabit LTE is again a marketing buzz, with the objective of achieving gigabit per second speed on LTE networks using more spectrum Carrier aggregation and MIMO techniques. So far the speed is tested have reached somewhat near to gigabits in highly optimized conditions like 264QAM etc.

Gigabit LTE is not about the peak data rates but more significantly the capacity enhancement of network, as three aggregated carriers perform better than if you run each carrier by itself.

With commercial availability, there will be UE terminals available in the market and their support will be driven by terminal sales figures and user experience. If Apple and Google believe CA and MIMO will make their users happier and buy more phones they will go for it. Same with LAA and new CBRS radios.

But things to be noted also that none really needs more than a few Mbps on a phone. Upper layers in the application stack aren't even designed for handling those peaks. Buffer sizes, screens etc. don't cope with 1Gbps. So the speed is of not much focus here for an end user (plus, your normal data cap would be used in half a minute).

Future networks will be built from inside buildings. The WAN to such a building is very seldom more than 1Gbps.  It's very often far less. So again, peak rates won't be the driver. Short latency, QoS, ability for a phone to seamlessly move between various radio network layers (for 100% mobility), private networks with access to local content which could require Gbps speeds, higher order antenna systems etc. are all features we will see in those 4G/5G networks.